Pregnane X receptor (PXR), a member of nuclear receptor superfamily, plays an important role in xenobiotic and endogenous metabolism, endocrine balance, and cell proliferation, etc. Previous study has shown that pregnenolone 16α-carbonitrile (PCN), a mouse PXR agonist, could induce liver enlargement. And we found that the change in hepatocytes exhibits regional distribution characteristics: hepatocyte enlargement occurs around the central vein (CV) area, while hepatocyte proliferation occurs around the portal vein (PV) area. In this study, the dynamic changes of hepatocytes during PXR-induced liver enlargement were determined. Serum and liver samples from male C57BL/6 mice were collected for biochemical and pathological analysis after PCN treatment for 1, 2, 3, 5 days, respectively. The animal experiment was approved by the Animal Ethics Committee of Sun Yat-Sen University. The results showed that with the increase in the PCN treatment days, the feature of this regional change of hepatocyte around the CV and PV areas became more and more obvious. At the same time, the factors related to hepatocyte enlargement, such as the expression of PXR downstream genes and the hepatic content of triglyceride (TG), has gradually increased. The upregulation of proliferation-related proteins and downregulation of cyclin-dependent kinases inhibitor proteins were observed in the early stage of PCN treatment, suggesting that hepatocyte proliferation occurs earlier than hepatocyte enlargement during PXR-induced liver enlargement. This study reveals the dynamic change of hepatocytes during PXR-induced liver enlargement and provides a new insight in liver enlargement promoted via PXR activation.

Pulmonary arterial hypertension (PAH), also named as a cancer of cardiovascular disease, is a rare disease and has complicated pathogenesis. Recently, there are more understandings of PAH pathogeneses. According to the pathogenesis and active pathways, the clinically used drugs are classified into several groups incluidng prostacyclin analogues and prostacyclin receptor agonists, endothelin receptor antagonists, phosphodiesterase-5 inhibitors, soluble guanylate cyclase inhibitors, etc. To elevate the efficacy of the drugs, numerous drug delivery systems are developed. This review mainly summarized the pathological mechanism of PAH, drugs and drug delivery approaches in the treatment of PAH.

Nucleocytoplasmic transport is the basic cellular activity of eukaryotic cells, which plays a role in cell physiological and pathological processes. A large amount of evidences indicate that impaired nucleocytoplasmic trafficking has emerged as a mechanism contributing to the pathology of neurodegenerative diseases. The regulation of nucleocytoplasmic transport is crucial to elucidate the pathogenesis and intervention in the neurodegenerative diseases. This article summarizes the evidences in disturbed nucleocytoplasmic transport of neurodegenerative diseases in the past two decades, further explores the directions and provides a theoretical basis for the pathogenesis and drug targets in neurodegenerative diseases.

To explore the effect and mechanisms of demethylation drug zebularine on esophageal cancer cells apoptosis, ECA109 cells and KYSE170 cells were treated with zebularine at different concentrations (25, 50, 100, 200, and 400 μmol·L^-1). The cell viability was measured by CCK-8. Flow cytometry was used to detect the cell apoptosis rate, Western blot was performed to determine the expression of apoptosis protein (Bcl-2, Bax, cleaved-caspase-3, and cleaved-PARP) and Wnt signal pathway molecules (β-catenin, cyclin D1, and c-Myc), real-time quantitative PCR was used to detect the expression level of negative regulatory genes of Wnt signaling pathway, methylation specific PCR (MSP) was used to detect the methylation status of secreted frizzled related protein 2 (SFRP2) and dickkopf 3 (Dkk3) genes. After knockdown of SFRP2 and Dkk3, the effect of zebularine on apoptosis was detected. The studies showed that zebularine could inhibit the activity of ECA109 and KYSE170 cells in a dose-dependent and time-dependent manner; zebularine could induce cell apoptosis, down-regulate the expression of Bcl-2 protein, up-regulate the expression of Bax, cleaved-caspase-3, and cleaved-PARP protein, and inhibit the expression of β-catenin, cyclin D1, and c-Myc protein (P < 0.05); the mRNA expression levels of Dkk3 and SFRP2 were significantly up-regulated by zebularine, while the methylation levels of SFRP2 and Dkk3 promoters were decreased; knockdown of SFRP2 and Dkk3 could reduce the apoptosis induced by zebularine. In summary, zebularine could reduce the methylation level of SFRP2 and Dkk3 gene promoter, promote the expression of SFRP2 and Dkk3 gene, and then induce the apoptosis of esophageal cancer cells by inhibiting Wnt/β-catenin signaling pathway.

Compound houttuynia mixture belongs to OTC class A medicine, which is made from Houttuynia cordata, Scutellaria baicalensis, Radix Isatidis, Forsythia, and Lonicera. As a kind of compound preparation of traditional Chinese medicine, houttuynia cordata mixture has extensive pharmacological effects, for example, clearing away heat and detoxifying, thus it is used for the sore throat, acute pharyngitis, and tonsillitis with wind-heat syndrome. In this study, the antiviral activity against influenza viruses and the primary mechanism of compound houttuynia mixture was evaluated. The antiviral effect of compound houttuynia mixture was determined by cytopathic effects (CPE), Western blot, quantitive reverse transcription PCR (qRT-PCR), and virus titer assays. The effect of houttuynia mixture on the replication cycle of influenza virus was evaluated by time-of-addition assay. In conclusion, the results showed that the compound houttuynia mixture had a broad-spectrum effect against influenza virus, including the international common influenza virus strains, the drug-resistant strains and the highly pathogenic avian influenza viruses H5N1 and H7N9. It mainly impairs the early stage of the viral replication.

Pneumonia caused by SARS-CoV-2 has seriously threatened human life and health worldwide and caused a large number of deaths. Viral infection and acute inflammation are important causes of death, so it is particularly important to combine antiviral therapy with anti-inflammatory therapy. Glycyrrhizic acid, the main component of the glycyrrhizic root extract, has a wide range of pharmacological effects as well as high efficiency and low toxicity, its preparation has been widely used in the treatment of chronic hepatitis and other diseases. Glycyrrhizic acid can regulate the expression and release of a variety of cytokines and play a significant anti-inflammatory effect. At the same time, glycyrrhizic acid also showed significant inhibition towards a variety types of viruses. Therefore, the potential application of glycyrrhizic acid as COVID-19 treatment should be explored.

Rheumatoid arthritis (RA) is an autoimmune disease with angiogenesis, inflammatory factor infiltration and joint destruction as the main pathological features. Angiogenesis promotes the development of RA and plays an important role in its pathogenesis. The hypoxia-inducible factor (HIF)-vascular endothelial growth factor (VEGF)-angiopoietin-2 (Ang-2) signal transduction is a critical pathway to induce synovial angiogenesis. Targeting HIF-VEGF-Ang-2 signal transduction to inhibit synovial angiogenesis is a promising approach for RA treatment. This article reviews the role and mechanism of HIF-VEGF-Ang-2 signal transduction-mediated synovial angiogenesis in RA, in order to provide a new target and strategy for RA treatment.

An UPLC-MS/MS method was established for the quantification of the genotoxic impurities bis(2-chloroethyl)amine hydrochloride and 1-(3-chloropropyl)-4-(3-chlorophenyl)piperazine hydrochloride in trazodone hydrochloride. The chromatographic separation of the two genotoxic impurities was performed on Waters ACQUITY UPLC BEH C18 column (100 mm×2.1 mm, 1.7 μm) at 20℃. A mixture of 5 mmol·L^-1 ammonium hydrogen carbonate aqueous solution and acetonitrile at a flow rate of 0.3 mL·min^-1 in gradient elution mode was employed as mobile phase. The UPLC-MS/MS was equipped with electrospray ionization in positive ionization mode and adopted multiple reaction monitoring mode. We found that the calibration curves of the two genotoxic impurities were linear in the range of 0.1-10 ng·mL^-1. The limit of detection was 0.10 ng·mL^-1 for bis(2-chloroethyl)amine hydrochloride and the average recovery was 101.53% (RSD=4.06%). The limit of detection was 0.01 ng·mL^-1 for 1-(3-chloropropyl)-4-(3-chlorophenyl)piperazine hydrochloride and the average recovery was 97.95% (RSD=1.27%). The sample solution was stable for 24 h. No bis(2-chloroethyl)amine hydrochloride was detected in the samples, and the content of 1-(3-chloropropyl)-4-(3-chlorophenyl)piperazine hydrochloride in the samples was within the limit. This research provides a method to improve the quality control standards of trazadone.

A metabolomics method was used to search for chemical markers in prepared slices of Glycyrrhiza uralensis with different degrees of honey processing. Coupled with these metabolomics analytical methods, ultra-performance liquid chromatography with quadrupole time-of-flight tandem mass spectrometry (UPLC-Q-TOF/MS) was used to generate global chemical profiles of the raw material of Glycyrrhiza uralensis and the prepared slices. The samples were collected in Shanxi, Hebei Zhangjiakou and Inner Mongolia. A total of 57 chemical components were identified in Glycyrrhiza uralensis by using the UNIFI theoretical database combined with the library of reference samples. Among them, 37 compounds were identified in positive ion mode and 56 compounds were identified in negative ion mode. Unsupervised principal component analysis (PCA) showed that the chemical ingredients differed considerably depending on the extent of processing. Supervised orthogonal partial least squares discriminant analysis (OPLS-DA) was used to differentiate the moderate processing group and the raw group, and partial least squares discriminant analysis (PLS-DA) was used to differentiate the less, the moderate, and the excessive processing groups. The results showed that the contents of glycyrrhizic acid, licoricesaponin G2, and licoricesaponin E2 varied with the extent of processing. The content of these components increased after processing, and reached the highest level when the extent of processing was moderate (P < 0.05). Glycyrrhizic acid, licoricesaponin G2 and licoricesaponin E2 can be regarded as the chemical markers to differentiate the samples with different degrees of processing. These three compounds can be used to monitor the processing of Glycyrrhiza uralensis.

Permeability is a key factor in the bioavailability of oral drugs. Therefore, in the early stage of drug discovery, accurate and efficient evaluation of drug permeability is essential. The parallel artificial membrane permeability assay (PAMPA) with Caco-2 cells model was used by the industry as early evaluation methods. At present, the Ussing chamber rat model is also widely used. This review summarizes the human data for the in vivo single-pass perfusion technique (Loc-I-Gut)-the gold standard, and then focuses on the basic principles, experimental operation, and efficiency of the three in vitro methods, with correlation to the effective permeability coefficient (P_eff) and fractional absorbed (Fa) in man. We provide recommendations for the use of proper permeability methods at different stages in drug discovery and development.